The most full-bodied top Riesling is opened from the case (7)
I believe the answer is:
richest
'the most full-bodied' is the definition.
I can't tell whether this defines the answer.
'top riesling is opened from the case' is the wordplay.
'top' says to take the initial letters.
'is opened from' becomes 'i' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'the case' becomes 'chest'.
The initial letter of 'riesling' is 'r'.
'r'+'i'+'chest'='RICHEST'
Can you help me to learn more?
(Other definitions for richest that I've seen before include "Most wealthy" , "extremely ornate" , "Least likely to be a beggar" , "Wealthiest" , "Most productive" .)